Joint media release: Innovative investment aims to protect giant cuttlefish

Senator The Hon Murray Watt, Minister for the Environment and Water
Peter Malinauskas MP, Premier of South Australia
Susan Close MP, Deputy Premier of South Australia, Minister for Climate, Environment and Water

The State and Federal Governments are investing in an intervention strategy aimed at safeguarding Australia’s iconic giant cuttlefish population from the algal bloom.

A 200m x 100m air bubble curtain will be installed on the Cuttlefish Coast in the Upper Spencer Gulf with an aim to protect about 50,000 to 80,000 cuttlefish eggs and hatchlings.

Air bubble curtain technology creates an underwater barrier that can mitigate the effects of algal blooms by disrupting the movement of algae, preventing it passing through the bubble curtain.

Bubbles are created using land-based generators and compressors to pump air through underwater feeder lines and tubing to create a buffer zone two metres to seven metres deep along the rocky reef.

Air bubble curtains have never before been used in South Australia, and the installation will be important trial of this technology.

It works as a preventative barrier, and is therefore ineffective for areas where the algal bloom has already been detected.

While bubble curtains have been successfully trialled in WA to protect kelp from fish, there are limitations to where and when they can be used. They won’t, for example, protect oysters from brevetoxins, nor can they be deployed across vast areas or in intertidal zones.

Installation of the air bubble curtain at Point Lowly, by East West Dive and Salvage, is expected to be completed this weekend, weather permitting. 

The algal bloom is present on the western side of Spencer Gulf and is moving north, but has not arrived at Point Lowly. 

The air bubble curtain will only be operational if and when the bloom is detected nearby.

The Department of Environment and Water and SARDI will monitor the site in consultation with cuttlefish and algae experts to determine when the curtain needs to be operational. Cuttlefish season has closed for the year.

Marine parks and harbour restrictions will be enforced through a 50 metre perimeter around the curtain. The site will be monitored by cameras and surveillance.

Cuttlefish eggs will start to hatch in late October through November. Dead cuttlefish are anticipated to wash up on the coast at the completion of the spawning season in coming weeks.

This is part of the natural cycle where cuttlefish die after spawning and should not be attributed to the algal bloom.

The latest giant cuttlefish counts show an estimated population at Cuttlefish Coast of 63,374, compared to 81,420 in 2024.

The lowest cuttlefish population estimate was approximately 13,500 in 2013. The highest population estimate on record is 247,146 in 2020.

Quotes attributable to Murray Watt:

“This rollout is another step to ensure that both governments are leaving no stone unturned when it comes to combatting the algal bloom.

“We are very hopeful the bubble curtain can make a difference during breeding season for the giant Australian cuttlefish, and are pleased to partner with the Malinauskas Government to fund this initiative.

“It builds on ongoing work to protect the viability of SA’s marine species, including a priority assessment by the Threatened Species Scientific Committee which could trigger the development of conservation plans for any species found to be under threat.”

Quotes attributable to Peter Malinauskas:

“The giant Australian cuttlefish is an iconic and spectacular creature, and the State Government is doing everything it can to ensure this precious population survives the algal bloom.

“We have taken significant advice from our Scientific Advisory Panel that this solution represents the best chance of protecting the species should the algal bloom arrive at the Cuttlefish Coast.”

Quotes attributable to Susan Close:

“Protecting this iconic species from the effects of the algal bloom requires innovative approaches and we are hopeful this technology can help preserve one of our states truly unique marine animals and the tourism it drives.

“However, the Government will continue to pursue measures recommended by scientific experts to help restore marine environments and protect species such as the giant cuttlefish.”

Quotes attributable to Eddie Hughes, Member for Giles:

“The giant cuttlefish are an iconic South Australian marine animal and they are of special significance to those of us that live in the Upper Spencer Gulf.

“I’m pleased we are able to provide this innovative measure to protect this important natural asset which brings joy to locals and visitors alike, and is an important driver of tourism to the region.”

Quotes attributable to Professor Mike Steer, Executive Director, PIRSA:

“The bubble curtain provides us with another tool to help protect unique and vulnerable marine species if required. 

“By investing in science-based technologies such as this, we hope to protect those species we know could still be adversely impacted, particularly during egg development and hatching.”